I realize that the judgement of when to place a screamer is up to personal preference. But I would like to hear some feedback from the community. I place my screws at a slight angle going up into the ice, or perpendicular and use screamers sparingly, when I think the placement is in questionable ice. But I have also heard of leaders using them at every screw. Any thoughts?

No, Ben. Sally is correct. The way to place ice screws is perpendicular or slightly upwards.

Sally, I also rarely use screamers, I only have one. Usually I am using double ropes though, so the impact force on one screw would be fairly low. However, I will sometimes use that screamer if a screw at a crux isn't that great.

I read that you should place it in a downward orientation so that the threads hold a fall, rather than torque from the weight of a fall. It also reduces shattering of the ice around the placement rendering a useless placement

If it faces up, the threads hold it. If it faces down, it will torque under a fall doing exactly as you describe and shattering the ice. You place it pointing slightly up.

I will place screamers for a number of reasons, afterall they are quick draws, so why not? However, I won't place them on the first screw, because if elongated (adding 1+ foot), could result in ground fall potential.

I typically will place them on my middle screws. High up, with more rope in the system the force factor is limited. So the higher up, the less force exerted on the top screws and the less need for force limiting screamers.

Example: I witnessed some dude at Vail climbing with bungee umbilicals shear the head off of his ice axe (cheap simond) but was caught by a non-screamered 10cm stubby BD screw. He was about 60 feet off the ground. Probably the craziest thing I have ever seen. All of the force of the fall rebounded into his axe that was in the ice above his head.

"This question was investigated by placing screws to the hilt at various angles. Perpendicular is chosen as the reference and labeled zero degrees. The conventional "place the screw at a 10 to 15 degree angle against the direction of pull" is a negative angle. Placing the screw in the direction of loading is labeled a positive angle, see Figure 1. As can be seen in Figure 2 there is a very dramatic change with angle of placement. What we observed is that placing the screw in the direction of loading is significantly stronger. In fact, at 15 degrees from perpendicular the screws are over two times stronger when placed in the direction of load than when placed against the direction of load. The data included in Fig. 2 is a compilation of all three lengths of Black Diamond ice screws using the highly variable test conditions described above. It is amazing that such a strong trend exists in such a variable experimental setup.

A general trend shows that screws are stronger when placed in the direction of loading. "

"The screws (BD style threads) actually are stronger when angled in the direction of the fall. The reason for this is that the threads do in fact have a high pullout strength. What I have seen is that the ice around the surface of a screw placed as you describe is the limiting factor. For a screw placed perpendicular to the surface or slightly angled back the top surface layer of ice breaks at fairly low loads (500 to 2000 lbs) and then you have the lever effect going on which is weaker. When the screw is angled down there is much less force on the top surface layer and it helps support the shaft so the screw does not flex and bend. However, placements are always limited by the ice quality. In "good" ice I think all screws will hold regardless of the angle (within limits of course)."

I used to place screamers on every piece of ice gear. I have opened one completely in a fall and think that without the screamer in place I would have decked. As it was I ended up hanging upside down looking my belayer in the eyes. After talking with the guys at Yates a couple of years ago they explained that as you get further out on lead the rope does more of the work. Now I carry enough for the first few pieces and switch to draws or runners after I have a good bit of rope out. I also choose to climb on lower dynamic impact force ropes for ice for the same reasons-- Lower then amount of energy being transmitted into the ice. Having used one and knowing that it saved my butt- I always carry and use screamers. I just don't carry as many as I used to. ie. Every piece Dallen

Screamers: A good rope has relatively low impact force (single, I don't use half ropes much except for low-angle alpine scrabbling, their impact forces are often too high to be worthwhile except for gentle falls), so unless the gear is super sketchy I don't use Screamers anymore. I work hard to get good ice gear, and retreat if I can't. The nebulous line between "maybe good enough" and "GOOD" is too fine for me. I want my gear to be good, or I either solo or go home. Bad gear leads to bad decisions for me, others may have more self-restraint. Gear is not meant to be jewelry, it's meant to be solid. Playing games with bad gear is seldom going to work out better than retreating if the movement isn't well within my skills. I used to believe "Some gear is better than none," but I'm moving more toward, "I like good gear, and will work hard to get it. If I can't get good gear then I go into solo mode, or retreat."

I read that you should place it in a downward orientation so that the threads hold a fall, rather than torque from the weight of a fall. It also reduces shattering of the ice around the placement rendering a useless placement

"This question was investigated by placing screws to the hilt at various angles. Perpendicular is chosen as the reference and labeled zero degrees. The conventional "place the screw at a 10 to 15 degree angle against the direction of pull" is a negative angle. Placing the screw in the direction of loading is labeled a positive angle, see Figure 1. As can be seen in Figure 2 there is a very dramatic change with angle of placement. What we observed is that placing the screw in the direction of loading is significantly stronger. In fact, at 15 degrees from perpendicular the screws are over two times stronger when placed in the direction of load than when placed against the direction of load. The data included in Fig. 2 is a compilation of all three lengths of Black Diamond ice screws using the highly variable test conditions described above. It is amazing that such a strong trend exists in such a variable experimental setup. A general trend shows that screws are stronger when placed in the direction of loading. " needlesports.com/catalogue/con... you guys need to read some books or something...ha ha

That graph clearly shows that the failure load is higher (ie takes more force to make the screw fail) if the screw is placed at a positive angle, ie with the tip placed upward. Craig Leubben showed similar results in drop test done in Boulder Canyon.

Reginald, Ben, what am I missing here? I'm pretty sure this is what Sally was saying:

I think Ben and Sally are saying the same thing. Sally says that she places at a slight angle going up into the ice. Ben says that he places in a downward orientation. If you look at the way it is placed in the video, the screw is angled slightly up going INTO the ice, thus positioning the crank downward coming OUT of the ice. You're both saying the same thing.

I have 6 and plan to use them first on every pitch even with double ropes. I'm scared shitless of actually falling on a screw and would like any mental cushion to trust my placement a little more. My mentor used a screamer on almost every screw and always emphasized the importance of low impact forces. I've seen screws hold 2000+lbs of force in pull tests on flat river ice, but I never get placements like that on climbs. Being the ice will always be of variable quality, I like to know I have that extra bit of security.

The angle of the screw, when IN the ice, should be below perpendicular with the ice...so I guess that means placing it upwards INTO the ice.

Pretend the screw is a line-segment, and the hangar of it is the end. The end of it should be below perpendicular when it is placed, so the threads hold the fall, NOT the torque strength of the screw (and the limited strength of the ice around it)